Peters



(No Model.)

A. JOHNSON. Mechanism for Transmitting; Motion.

Patented Oct. 19, 1880.

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ASA JOHNSON, OF NEW YORK, N. Y., ASSIGNOR OF TWO-THIRDS OF HIS RIGHT TO VILLIAM W. GIBBS, OF SAME PLAGE, AND ANSON F. FOWLER, OF MIDDLETOWN, OONN., ONE-THIRD TO EACH.

MECHANISM FOR TRANSMITTING MOTION.

SPECIFICATION forming' part of Letters Patent No. 233,518, dated October 19, 1880.

Appnan0nh1ea1iramh1n, 1880. (No model.)

transmitted from one shaft to another, as hereinafter fully set forth.

Figure 1 of the drawings annexed presents a sectional side elevation of myimproved mechanism applied to a steam-engine for changing the reciprocating motion of its piston into a continuous rotary motion of the driving-shaft. Fig. 2 is a plan view of the same, and Fig. 3 is a transverse section thereof.

My invention is designed more especially for steam or other engines as a substitute for the crank and connecting-rod, whereby the motion of the piston may be imparted directly 'and in a tangential line to the driv-*ing wheel i or shaft, and in such manner, also, as will obviate all dead-points and admit of reversing the motion of the shaft without changing the valve of the engine.

To this end a leading feature of my invention consists in connecting the reciprocating bar or piston-rod with two or more frictionclutches, each acting alternately and in opposite directions on friction rims or hubs on two or more distinct wheels, which are geared together, whereby a continuous rotary motion is imparted to the wheels by the alternating bite of the clutches.

Another feature of my invention lies in the special form of these clutches, and also in a means of shifting these clutches, whereby the direction of their bite on the friction-rims becomes reversed, and accordingly reverses the direction of rotation.

In the drawings, c c indicate the shafts to which the power of the reciprocating piston or other motor is imparted, one of which may serve as the driving-shaft, from which a train of machinery may be driven; but both shafts may be so used, if desired. These shafts are geared together by the toothed wheels b b, which are fixed on the shafts. The frictionclutches, which are reciprocated by the pistonrod or other reciprocating bar, act on frictionrims or purchase-wheels cc, which are also fixed on the shafts da or to the gear-wheels b, so as to revolve therewith. These wheels are preferably formed as plate-wheels with a thin central web and a projecting rim on each side of the web at the periphery, as seen best in Fig. 3, and their diameter is nearly as large as the gear-wheels, or as large as practicable, so as to obtain greater leverage.

The friction-clutch consists of a radial arm, d, which is mounted loosely on the hub ofthe purchase-wheels, or on the shafts thereof, and carries at its outerends two friction-shoes, cc, which embrace, respectively, the inner and outer face of the rims on the purchase-wheels, and are pivoted at or about the center to the arm d, as seen best in Fig. 1. Now, the crosshead on the piston-rod of the engine connects to a straight reciprocatin bar, f, which is guided at vits outer end in the guide g, and is connected midway with each of the clutch-arms d d, the said bar having notches which fit over pins h, projecting from the clutch-arms, as shown in Fig. 1, so that the reciprocation of the piston correspondingly reciprocates the clutches in short circular arcs.

In this kind of engine I prefer to have the diameter ot' the piston large and its stroke small, so as to be able to transmit a great power through the clutches, but in short arcs, so that the clutch movement will approximate closely to straight lines, as will be readily understood. f

It win be Observed from rig. 1 that the inl each purchase-wheel inclines in opposite directions, so that when the piston-rod or reciprocating bar moves forward, one of the clutches bites and the other slips, while both wheels revolve by the power applied to one, and when the rod or har moves backward the second clutch bites upon the other wheel, while the first slips; but it will be observed that as both wheels are geared together these alternate clutchings on each wheel cause both wheels to revolve continuously and in the same direction with a uniform and steady motion.

The clutches, as may be perceived from Fig. l, bite by an eccentric or cramping action of the friction-shoes upon the rims of the purchase-wheels, which occurs only when the clutch is moved in the direction toward which they4 incline, and the shoes relax and move loosely over the rims when moved in the opposite direction. The bite of the shoes is such as to gripe the rim inan instantaneous and positive manner, yet without denting the rims or being liable to slip when advancing or catch when retiring.

It will be observed that by this form of transmitting mechanism the power of the piston is transmitted in a direct line to the long end of the lever, and without any dead-points in its movement, as is the case with the crankmotion in which the power is applied in a direct line to the center of the shaft, and in which', also, the piston-rod has to stop and wait at the dead-points for the crank to be carried a long distance by the momentum alone, which is not the case with my transmitting mechanism. Moreover, by this mechanism the rotation of the driven shaft does not react upon the piston, but the momentum of the driven shaft and its wheels may continue the rotation when the movement of the piston ceases, thus allowing intervals of rest to the piston, it' required, to further economize the power.

Another advantage of this mechanism is, that by shifting the clutches by the movement of a hand-lever, the rotation of the drivingshaft may be instantly reversed without chan ging the valve of the engine. rlhe clutches are accordingly shifted and held in either of their acting positions by forked levers t' t', pivoted below the purchase-wheels, while their forked ends embrace the slotted pivotal ends of the clutch-arms d, as seen bestin Fig. 1, and these levers are connected, by links k It, to the short arms of a long hand-lever, Z, which projects above the bed of the engine in convenient position for operation by the hand. This lever, when shifted to one side or the other, catches on either side of a stop, m, Fig. 2, which holds the clutches in the required position, and it will he observed that the effect of shifting the clutches to one side or th'e other is to throw the pivot-line of the friction-shoes eccentric to the axis of the purchase-wheels, as seen in Fig. l, which, hence, causes the shoes to gripe when moved toward the longer radius of the eccentric and slip in the opposite gearing into one of the gear-wheels b. This I eccentric is also connected directly with the bar el by a slotted link, u', which connects with a crank-pin on the pinion n, while its slotted end engages with a pin on the bar d. The valve-stem may also be operated by a lever, 0, one arm of which projects over the bar d, and is struck by adjustable stops d d thereon at each end of the stroke, so as to actuate the valve iu the proper manner. This lever is slotted, and is mounted on an adjustable fulcrum, r, by'adjusting which the stroke of the valve may be lengthcned or shortened, thus giving it more or less lap or lead, and thus enabling the cut-oftl to he regulated, as desired, in a simple manner. 1

The described form of transmitting mechanism is obviously adapted for many purposes other than engines where a reciprocating motion is to be converted into a rotary motion, and the described clutch may also he employed in various kinds of machinery, either for transmitting or converting a reciprocating motion, or for transmitting a continuous rotary motion from one shaft to another. It may thus be employed in treadles, friction-pulleys, carstarters, Ste.

It will be observed that the arrangement of gear-wheels and clutches is double, as seen best in Figs. 2 and S-that is, the purchasewheels are arranged between two gear-wheels which mesh together, and a clutch is arranged on each side ofthe purchase-wheels, the clutcharms d d being joined together by the connecting-pins 7L, which engage with the reciprocating bar, but only a single set of gearwheels and clutches may be used, when preferred, and the friction-rims on which the clutches act may be formed directly ou the gear-wheels themselves.

In the form of steam-engine illustrated I prefer to employ a novel form of valve, as seen best in Fig. 2. In this valve the valve-chest is a little longer than the cylinder, and from its eXtreme ends the steam-ports extend 'directly into the ends of the cylinder. Close to these steam-ports independent exhaust-ports extend, on a slight incline, to the valve-seat, opening between the steam-ports, as shown. The valve is made in two sections moving in the ends of the valve-chest, and each long enough to cover one exhaust-port when the adjacent steam-port is open, and vice versa, as illustrated. Now, these valve-sections move steam-tight between the valve-seat and a fixed overlying plate, over which the steam has ac- IIO IZO

cess to the steam-ports and valve only at each end, so that by this means only that part of the valve which projects beyond the overlying plate and covers the steam-port is exposed to the steam-pressure, which, being partly counteracted by the pressure from within the cylinder, thus renders the valve nearly balanced.

The valve-stem is made in two parts, a solid and tubular part, each connected to a distinct section of the valve and movable within or on the other, so that by extending or contracting the stems the valve-sections will be set farther apart or closer together, thus regulating the cut-off action of the valve to any required degree. The valve-stems are connected together at the required point by a pin passing through both or by a screw-connection.

A nunber ofA pin holes may be formed through the stems to admit of holding the valves at different adjustments but I prefer to accomplish this adjustment by a screw movement, by threading the ends of the valvestems and screwing them into the valve-sections, as illustrated.

To regulate the stroke of the valve to correspond to the spreading or contracting of the sections, the fulcrum of the lever or the stops d on the bar d may be adjusted so as to give the valve the proper stroke.

The overlying valve-plate is made in the form of a case, which incloses the valve steamtight except at the ends, and is ordinarily fixed to the valve seat or chest by bolts, as seen best in Fig. 4 5 but by detaching it from the valve-seat and screwing it to each of the valve-sections the valve will then be converted into a common slide-valve.

What I claim as my invention is- 1. A reversible friction-clutch for transmitting motion or pressure, consisting of a frictional purchase wheel or rim, in combination with a radial arm movable freely from the axis of the wheel and shiftable at its pivotal end, so as to incline in either direction, together with a friction shoe or shoes mounted on the outer ends of said arm and engaging with the said friction-rim, substantially as herein shown and described.

2. Mechanism for transmitting or converting motion, consisting of two or more frictional purchase wheels or rims geared together, in combination with two or more friction-clutches connected with the reciprocating bar or motor, and each engaging with one of the wheels and arranged to bite alternately in opposite directions on each wheel, whereby a continuous rotary motion is imparted to the two wheels, substantially as herein shown and described.

3. A friction-clutch for transmitting motion or pressure, consisting of a frictioual purchase wheel or rim, in combination with a radial arm moving freely from the axis of the wheel, and provided with two cramping friction-shoes at its outer end, each embracing, respectivel y, the concave and convex faces ofthe friction -rims, substantially as herein shown and described.

4. A reversible friction-clutch consisting of a frictional purchase wheel or rim, with a friction shoe or shoes engaging therewith, and a radial arm carrying said shoe or shoes at its outer end, and having its inner pivotal end slotted and capable of being shifted from one side to the other, together with a means of thus shifting the said arm, substantially as herein shown and described.

5. A slide-valve madein two sections, separable or contractible, tol regulate the cut-oft' action, in combination with a valve-seat provided with exhaust and steam ports arranged adjacent to each other at each end of the chest, and both extending from the face of the seat directly -into the cylinder, the said valve-sections being formed without cavities and long enough to cover the exhaust-port when the adjacent steam-port is open, and vice versa,

substantially as herein set forth.

6. The combination, with a slide-valve, of a iixed overlying plate or casing inclosing the valve steam-tight, except at each end, and fixed to the valve-seat, substantially as and for the purpose herein shown and described.

7. In a reciprocating engine, a valve-operating lever mounted on an adjustable fulcrum, whereby the stroke of the valve may be regulated as required, in combination with a reciprocating piston rod or bar and projections thereon arranged to move the said lever at each end of the stroke and operate the valve, substantially as herein set forth.

4ASA JOHNSON. Witnesses: p

EDWARD H. WALES, CHAs. M. HIGGINs. 

